1. Field of the Invention
This invention relates to a method for preventing caking of surfactants that have a tendency to cake, to granular or powdery detergent compositions containing as an active ingredient such a surfactant, and to non-caking powdery or granular detergent compositions. More specifically, this invention relates to the use of a special anti-caking agent composition for reducing the caking tendency of granular or powdery detergent compositions containing one or more surfactants that have a significant tendency to cake, such as alkylethoxy sulfates, alkylphenylethoxy sulfates, branched alkyl sulfates, alkane sulfonates, vinylidene-type olefin sulfonates, internal olefin sulfonates and ethylene oxide-type non-ionic surface active agents.
2. Description of the Prior Art
Caking of powdery or granular detergent compositions has a bad influence not only on the detergent-manufacturing steps, but also on the handling of the detergent composition when it is put into practical use for clothes-washing in housholds. This caking phenomenon seriously reduces the commercial value of powdery or granular detergent compositions. Therefore, it is very important to overcome this tendency of caking of powdery or granular detergent compositions.
The tendency toward caking of a granular or powdery detergent is greatly influenced by the kind of the surfactants employed therein. Some satisfactory compositions are known. For example, sodium benzene sulfonate and sodium toluene sulfonate have a good effect for preventing caking in branched alkyl benzene sulfonates, and sodium sulfosuccinate is similarly effective for linear alkyl benzene sulfonates. However, it is said that sodium sulfosuccinate is not effective for the former type surfactants, and sodium benzene sulfonate and sodium toluene sulfonate are not effective for the latter type surfactants.
Although the surfactants that have a significant tendency to cake, exemplified in the first paragraph of this specification above, have an excellent washing activity, granular or powdery detergent compositions containing such surfactants are likely to cake and their commercial values are thereby seriously reduced.